Airborne valves are commonly deployed aboard aircraft to regulate fluid flow. An airborne valve, and specifically the material from which the flowbody of the airborne valve is cast, ideally has relatively low density, is highly durable, and is highly ductile. When intended to operate in lower temperature environments, airborne valve flowbodies are commonly cast from aluminum and aluminum-based alloys, which generally satisfy the foregoing criteria. However, when the airborne valve is to be utilized within higher temperature environments (e.g., approaching and possibly exceeding approximately 1,200° Fahrenheit), such as when the airborne valve is used to regulate compressor or combustive gas flow from a gas turbine engine, aluminum and aluminum-based alloys are typically unsuitable as flowbody materials due to operational temperature limitations. For this reason, it is conventional practice in aerospace industry to cast high temperature valve flowbodies from high-strength, refractory metal alloys, such as 17-4PH stainless steel or Inconel 718®. Although durable and relatively ductile, such refractory metal alloys have relatively high densities (e.g., the densities of 17-4PH stainless steel and Inconel 718® are approximately 7.74 grams per cubic centimeter (g/cm3) and 8.22 g/cm3, respectively). Airborne valve flowbodies cast from such high temperature materials are consequently undesirably heavy for utilization in airborne applications.
Titanium aluminide alloys have relatively low densities and have been utilized to fabricate certain dynamic components deployed within gas turbine engine, such as air turbine blades. However, titanium aluminide alloys have long been considered excessively brittle for use in the fabrication of high temperature airborne flowbodies, which serve as pressure vessels that conduct highly pressured fluids during operation (e.g., pressured bleed air having pressures exceeding several hundred pounds per square inch (psi) and commonly approaching 600 psi). Titanium aluminide alloys have also been utilized to produce certain non-pressure containing valve components (e.g., poppet-type valve elements) for other ground-based pneumatic systems, such as for automotive internal combustion engines. Titanium aluminide alloys have not, however, been utilized to produce static, pressure-containing valve flowbodies in any context of which the present inventors are aware. Furthermore, in the terrestrial applications set-forth above, the operational requirements, the valve types, and the valve designs are markedly disparate from the high temperature, high pressure airborne valve flowbodies utilized in the aerospace industry.
There thus exists an ongoing need to provide embodiments of a high temperature airborne valve having a reduced weight as compared to conventional airborne valves produced utilizing high density material, such as 17-4PH stainless steel and Inconel 718®. In accordance with embodiments of the present invention, and as described in the subsequent sections of this document, this ongoing need is satisfied by providing airborne valves including lightweight flowbodies formed, at least in part, from titanium aluminide. It would also be desirable to provide one or more methods for manufacturing such lightweight, high temperature airborne valves. Other desirable features and characteristics of the present invention will become apparent from the subsequent Detailed Description and the appended claims, taken in conjunction with the accompanying drawings and this Background.